Post mortem NodeJS debugging
summary
Uses llnode on an LLDB core dump paired with the exact Node binary to recover JavaScript stacks (v8 bt, v8 inspect, frame select) and to find retained objects; generates cores with ulimit and node --abort-on-uncaught-exception or kill -SIGABRT and writes heap snapshots via SIGUSR2 (Node v11.13+) for Chrome DevTools diffing. Demonstrates CPU sampling (≈9 probes/sec) and uncovers a leak of about 235,000 visit objects. Notes missing tooling: no direct core→heap-snapshot converter yet, but heap dumps from signal do work.
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chapters (9)
- 0:00Start
- 1:36What Is Post-Mortem Debugging
- 4:29Memory Dumps
- 9:47Crashes
- 16:17Unresponsive Process
- 18:33Cpu Profiling
- 18:54Recap
- 23:10Find Refs
- 26:38Comparison Mode
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